ds.elspline: Basis for a piecewise linear spline with meaningful...
In datashield/dsBaseClient: DataSHIELD Client Functions

ds.elspline

R Documentation

Basis for a piecewise linear spline with meaningful coefficients

Description

This function is based on the native R function elspline from the lspline package. This function computes the basis of piecewise-linear spline such that, depending on the argument marginal, the coefficients can be interpreted as (1) slopes of consecutive spline segments, or (2) slope change at consecutive knots.

Usage

ds.elspline(
  x,
  n,
  marginal = FALSE,
  names = NULL,
  newobj = NULL,
  datasources = NULL
)

Arguments

`x`	the name of the input numeric variable
`n`	integer greater than 2, knots are computed such that they cut n equally-spaced intervals along the range of x
`marginal`	logical, how to parametrize the spline, see Details
`names`	character, vector of names for constructed variables
`newobj`	a character string that provides the name for the output variable that is stored on the data servers. Default `elspline.newobj`.
`datasources`	a list of `DSConnection-class` objects obtained after login. If the `datasources` argument is not specified the default set of connections will be used: see `datashield.connections_default`.

Details

If marginal is FALSE (default) the coefficients of the spline correspond to slopes of the consecutive segments. If it is TRUE the first coefficient correspond to the slope of the first segment. The consecutive coefficients correspond to the change in slope as compared to the previous segment. Function elspline wraps lspline and computes the knot positions such that they cut the range of x into n equal-width intervals.

Value

an object of class "lspline" and "matrix", which its name is specified by the newobj argument (or its default name "elspline.newobj"), is assigned on the serverside.